Allergen Control: How to Use Your HVAC System to Combat Indoor Allergies

If you struggle with indoor allergies, life can be miserable. Indoor pollution can be as bad – if not worse – than outdoor pollution, leaving you sneezing, stuffy, and uncomfortable. However, you have a secret weapon: your HVAC system.

Bell Brothers has been serving homeowners in Sacramento, Hayward, and Concord with their HVAC needs for decades. Including indoor air quality. With the World’s Friendliest Technicians℠ and 9 guarantees for HVAC maintenance, repairs, and installation, we have your back.

But in the meantime, here are our tips to make your HVAC system work for you and combat your indoor allergies.

The Connection Between Allergens and HVAC Systems

Allergies are a common concern for many people. Both indoor and outdoor allergies can create an immune response that causes unpleasant symptoms. common indoor allergens include pet dander, dust mites, mold spores, pollen, and cockroach droppings.

The main sources of indoor allergens include:

  • Pets
  • Wall-to-wall carpet
  • Soft furniture
  • Damp areas
  • Bedding
  • Stuffed toys
  • Mattresses without allergy covers
  • Pillows and bedding that can’t be washed in hot water
  • Indoor plants

in many cases, more allergens are found on surfaces than in the air. Then, when you disturb them by sitting, lying, or moving around, they circulate in the air and may end up in your HVAC system.

When these allergies are combined with high humidity levels, poor ventilation, and low air circulation, you end up with a higher concentration of allergens – and worsening by extension.

Because of this, your HVAC system plays a bigger role in maintaining indoor air quality than you may realize. Adjusted properly, it can alleviate your indoor allergies. Without care, however, you could end up with severe symptoms.

Here’s the connection between your HVAC system and allergies:

  • Air filters: Your HVAC system has air filters to trap pollen, dust, pet dander, and other common allergens. If you neglect your air filters and don’t clean or replace them as needed, they may become clogged with allergens. Then, these allergens circulate around your home.
  • Humidity control: The level of humidity in your home affects allergens. For example, HVAC systems that maintain the ideal humidity levels in your home can prevent mold growth, which is a common source of allergies for many people.
  • Ductwork: Dirty or leaking ducts can circulate allergens throughout your home. When dust and mold spores build up in the ducts, your HVAC system blows them all through your living spaces.

Here are some tips to make your HVAC system work for you:

Choose the Appropriate HVAC System

It’s important to get an HVAC system that helps with allergen prevention. High-efficiency particulate air (HEPA) filters can trap small particles, including common allergens, to make your indoor air cleaner. You should also evaluate the ventilation rates and humidity control features your HVAC system has, which can prevent the proliferation of mold and dust mites.

Schedule Regular Maintenance

HVAC systems should be maintained to function properly. If you neglect your system – particularly with cleaning – they become an ideal space for mold, bacteria, and other allergens to grow. The filters that are responsible for trapping these airborne particles become saturated with allergens over time, so they can no longer capture new particles. Eventually, they will release the built-up allergens back into your home, so they should be replaced or cleaned regularly to maintain their effectiveness.

Along with filters, your ductwork and coils should be inspected and cleaned regularly. Ducts accumulate dust, mold, and other household contaminants, which will eventually get blown back into your home. If any ducts have leaks, they need to be repaired to avoid the ducts sucking contaminants in from the crawl space, attic, or basement. Regular maintenance ensures that your system functions at its best and keeps your indoor air as clean as possible.

Optimize Your Humidity Levels

Keeping your humidity levels ideal is important for allergy prevention. If it’s too high, you could end up with a high dust mite population and mold growth. However, if it’s too low, you may have irritated airways that worsen your allergy symptoms.

Some HVAC systems have humidity control features, such as dehumidifiers, that help you maintain the ideal balance in your home, which is between 20% and 50%. This limits allergens and ensures you have healthier indoor air.

Improve Air Filtration

As mentioned, HEPA air filters can capture the smallest allergens like dust mites, pet dander, and pollen, to reduce them in your indoor air. If your HVAC system doesn’t have a HEPA filter, invest in a standalone HEPA filter.


If it’s time for an upgrade, consider getting a HEPA filter with a higher minimum efficiency reporting value (MERV) rating to capture more particles. This measures how well an air filter traps particles between 0.3 and 10 microns. MERV ratings range from 1 to 20, the higher numbers indicating better filter performance. A rating of 8 to 10 is ideal for people with allergies or pets.

Other Allergy Tips

Your HVAC plays a big role in indoor allergies, but it’s not the only factor. Here are some tips to help with indoor allergies:

Choose Allergy-Friendly Flooring and Furnishings

Indoor allergens come from a lot of places, including the materials used in your home’s construction, your furniture and carpeting, and more. These materials can harbor dust mites, mold, and pet dander that circulates through the air.

If you have allergies, choose hard flooring and area rugs that you can easily wash and disinfect to reduce allergens. You should also choose hypoallergenic bedding and furniture that can reduce allergens in your home, particularly while you sleep. Allergen-resistant covers for your mattress and pillows can limit the dust mites that accumulate in your bedding, and they’re much easier to wash regularly.

Clean Surfaces

Just like your ducts and air filter, allergen particles accumulate on surfaces in your home, eventually ending up back in the air where you can breathe them in. They may go into the HVAC system as well, only to be recirculated through your home.

Get in the habit of vacuuming and mopping hard floors regularly. If you have carpeting, vacuum often and steam your carpet every few months to reduce allergens. With area rugs, regular washing can help keep allergens at bay.

Hard surfaces like tables should be dusted regularly to dispose of contaminants. If you have upholstered furniture, remove the cushions and vacuum and steam the upholstery on a regular basis.

Limit Pet Dander

Doctors recommend that people with allergens not have pets with fur or feathers, but many people live allergies and keep pets. While there’s no such thing as a hypoallergenic pet, you can reduce allergens by keeping up with your pet’s dander.

Make sure you bathe and brush your pets regularly to limit pet fur ending up on your furniture and floors. Wash your pet’s bedding regularly to cut back on hair and allergens. If possible, close the doors to some rooms in your home to keep pets out. Try not to allow your pet to sleep in bed with you, as this can aggravate your allergies while you sleep.

Pets with long hair can bring pollen inside on their hair during the spring and fall. During these seasons, be more diligent about brushing and bathing to reduce the allergens that enter your home. Wear a mask while grooming to avoid breathing them in.

Limit Mold Growth

Mold spores can be a significant source of allergens. Reduce moisture in your home, particularly in the bathroom, kitchen, and other areas where there is a lot of water. Here are some tips:

  • Don’t run showers for a long time before bathing.
  • Use humidity monitors in wetter areas of your home to track humidity levels.
  • Use dehumidifiers to reduce both mold and dust mites.
  • Fix all leaks and other causes of damp areas.
  • Limit yourself to just a few house plants. While they can filter your air naturally, plants naturally add humidity.
  • If you spot mold, clean it immediately. Wear a mask and clean the surface once a week to ensure it doesn’t return.

Control Cockroaches

Cockroach droppings can trigger allergies in some people. Keep food or garbage covered and avoid having too much clutter in your home, especially in dark, damp areas, that can attract cockroaches. Try traps and boric acid to eliminate infestations without the use of harsh chemicals that may irritate your sinuses and asthma.

Improve Indoor Ventilation

Proper ventilation is an important part of reducing indoor air pollution. In addition to your HVAC system, open your windows and use your exhaust fans in your bathrooms and kitchen to allow more fresh air in. Doing so can prevent the buildup of indoor allergens and improves your indoor air quality.

Reduce Indoor Allergens with Your HVAC

Indoor allergens are a fact of life, but your HVAC can work for you. If it’s time to upgrade your HVAC system or get routine maintenance to ensure everything is working as it should, contact the pros at Bell Brothers and schedule your appointment!